Regenerative Endodontic Treatment Using Periapical Blood or Circulating Blood as Scaffold: A Volumetric Analysis

Introduction: Circulating blood is a readily available scaffold when enough bleeding cannot be induced from periapical tissues during regenerative endodontic treatments (RETs). The aim of this investigation was to compare the radiographic outcome (ie, linear and 3-dimensional volumetric) of RET using periapical blood or circulating blood as scaffolds in sheep immature mandibular incisors. Methods: Thirty-two immature sheep mandibular central incisors were randomly assigned to the following groups (n 5 8): the positive control groups, the pulps were removed without any treatment; the periapical blood group, RET was performed using periapical blood as the scaffold; the circulating blood group, RET was performed using circulating blood as the scaffold; and the negative control group, intact teeth without any treatment. After 8 months, micro-computed tomographic images of mandibular blocks were taken to assess the following: root length, root thickness at the midroot and cementoenamel junction levels, and the incidence of apical closure. Root structures were segmented, and root volumes were calculated and analyzed statistically. Results: RET using periapical blood and circulating blood resulted in increases in root length and root wall thickness at the midroot and cementoenamel junction levels, the incidence of apical closure, and root volume (P < .05). There were no significant differences between the RET groups and the negative control group regarding linear measurements (ie, root length, root thickness, and apical closure) (P > .05). The root volumes of the 2 RET groups were similar (P > .05) and were less than those observed in the negative control group (P < .05). Conclusions: There were no significant radiographic differences between the RET groups using periapical blood and circulating blood as scaffolds. RET resulted in less root volume compared with normal root development.